Field
The disclosed technology generally relates to semiconductor devices, and more particularly to a device configured to generate and/or detect spin waves.
Description of the Related Technology
With the ongoing technological advances, there is a constant desire to increase the speed and processing power of transistor-based computational architectures. For the past 40 years, miniturization, or scaling, of field-effect transistors and integrated circuits has provided ever-increasing transistor performance and density, following the famed Moore's law, which predicts that the computational power doubles roughly about every 18 months.
To continue the scaling or miniturization in the next decade(s), an extensive international research effort is currently being undertaken, with a strong focus on replacing Si-based field-effect transistors with devices with similar or identical functionality with improved performance.
It is, however, widely acknowledged in the semiconductor community that the miniturization of conventional devices, such as complementary metal oxide semiconductor (CMOS) transistors is becoming increasingly challenging, and for many applications, there is an increasing need for alternative device structures. The difficulty in scaling devices such as CMOS transistors arises from several concurrent fundamental and practical limits related to their operation and manufacturability. For example, one limitation is the increase of the dissipation power, which has emerged as one of the main challenges hampering further improvement. Hence, there is a need to limit thermal dissipation, which becomes critical when scaling down feature sizes of a transistor, e.g., the gate length of a transistor, to the nanometer regime. In the nanometer regime, among other effects, quantum mechanical effects, can drastically increase leakage currents.
The utilization of electron spin for information encoding and information transmission offers an attractive solution. Spintronics is an emerging new approach to electronics, where the information is carried out by the spin of the carrier, in addition to the charge.
To this end, spin wave-based logic and signal processing devices may further be used to replace conventional charge-based microelectronic circuits. For spin waves, phase and amplitude may be controlled by gating it with local electrical and magnetic fields. Unlike some traditional devices such as field-effect transistors that utilize movement of charge carriers (e.g., electrons and/or holes), using spin waves to compute does not require moving charge. The wave properties of the spin waves, such as their ability to interfere, may further be used to efficiently perform logical operations. In addition, unlike some devices utilizing optical computing, spin wave wavelengths are not limited to the wavelength of light. For these reasons, among other reasons, spin wave-based devices may be better adapted for scaling to the nanometer scale.
A successful realisation of spin wave circuits depends, however, crucially on the efficiency by which spin waves may be generated or detected.